Method for the decomposition of alkali-metal minerals



UNITED STATES PATENT OFFICE.

EINAR IBERGVE, OF NOTODDEN, NORWAY, ASSIGNOR T0 NOBSK HYDRO-ELE'KTRISKKVAELSTOFAKTIESELSKAB, OF CHRISTIANIA, NORWAY, A JOINT-STOCK COM- PANYOF NORWAY.

METHOD FOR THE DECOMPOSITION OF ALKALI-.METAL MINERALS.

No Drawing.

To all whom it may concern:

Be it known that I, EINAR. Bnnovn, subject of Norway, residing atNotodden, Norway, have invented new and useful Improvements in Methodsfor the Decomposition of Alkali-Metal Minerals; and I do hereby declarethe following to be a full, clear, and exact description of the same.

Through the action of sulfur vapor upon alkali metal silicates a partialreduction of chemically combined oxygen will take place, sulfa-silicatesbeing formed, for instance potassium feldspar.

K O.Al O .*6SiO is treated with sulfur vapor, the K 0 already at a proortionally low temperature (below 1000 8.) will be converted into K 3 asthis reaction is exothermic. If the temperature is further increased theendothermic reaction 5. e. the reduction of A1 0 into A1 9; will alsocommence. These two sulfids combine with SiO formingoxy-sulfo-silicates. When a sufiiciently high temperature is used theSiO may also be converted into SiS which together with the sulfobasesforms sulfo-silicates, as above mentioned. Temperatures of about 800 to1400 C. will be found satisfactory.

These sulfo-silicates 0r oxy-sulfo-silicates may be decomposed withwater underpressure and at high temperature so that the Specification ofLetters Patent.

Patented July 13, 1920.

Application filed April 30, 1919. Serial No. 293,876.

alkalis are obtained in solution. It has however also been observed thatsulfo-silicates and oxy-sulfo-silicates at common pressure andtemperature can be decomposed by even the weakest acids.

The present process may be carried out gases may be used, which areobtained in several metallurgical processes for instance in the meltingof pyrite in order to obtain coo er-matte.

aving now described my invention, what I claim as new and desire tosecure by Let ters Patent is:

1. The method of decomposing alkali metal silicates, which consists insubjecting the silicate to the action of sulfur vapors at temperaturesof about 800 to l400 C.

2. A method according to clalm 1, in which decomposition takes place inan atmosphere containing sulfur and sulfur diox d.

In testimonywhereof, I have signed my name to this specification in thepresence of two subscribing witnesses.

EINAR BERGVE.

Witnesses AXEL LAHN, HAROLD LAHN.

quite as effectively if the sulfur vapors are mixed with S0 also thesulfurous roast

